1. Field of the Invention
The present invention relates to a roll winding device and process, e.g., for a reel slitting device, that includes a roll support device and a pneumatic pressure release device.
2. Discussion of Background Information
A roll winding device similar to the device generally discussed above is known, e.g., from DE 195 24 905 A1, for use with material webs, e.g., paper webs.
In one of the last manufacturing steps, paper webs are usually cut or slit into a desired widths or partial webs and wound into rolls before they are packed and delivered to consumers. In contrast to the reel-spools which are used during paper production, the cores upon which these rolls are wound have a relatively low stiffness and bearing capability, and are generally cardboard tubes. Thus, the paper rolls are normally supported by support rolls during winding. This is particularly true if the winding device is a carrier roll winder in which the roll lies on carrier rolls without additional holding forces being applied on the core. However, even with a back-up roll winder, in which additional holding devices are used to hold the roll at its core, the roll rests on the back-up roll. As the paper rolls become larger and heavier, the line force of the paper roll on the support roll or rolls become increasingly larger. Thus, the roll density is likewise increased, which may disadvantageously lead to damage to a support roll. To unburden the support rolls and to reduce the line force, pneumatic overpressure can be produced underneath the paper roll, so that the paper roll is resting, at least partially, on air cushions.
The above-described pneumatic overpressure procedure has been utilized in the art to unburden the support roll. However, due to the changing geometry of the paper roll, a relatively large amount of pressurized air is required. Nevertheless, due to the escape of the air, forming the air cushion solely using the pressurized air is difficult.